Old Bulbs = Nuisance Algae?

[Lance]

I run 250W 10K MH, 10K T-5 and pure actinic T-5. Lately I too was getting a lot of film algae on the front glass only, (having to clean it every day). Phosphate levels were fine. I checked the age of the front T-5 and noticed it was 11 months old, so I replaced it Saturday with a new URI 10K and replaced the actinic with a Fiji purple. Haven't had to clean the glass since. (Mind you its only been 2 days). Just a coincidence? I don't think so. The new light had to have had something to do with it.